Nintendo confirms theory that select Switch games won't get cloud save support due to item duplication issues
Earlier today, we learned that a handful of Switch games would not be getting Switch save data cloud backup support. A theory started to go around stating that this had something to do with item duplication issues. Turns out that theory was right on the money, as Nintendo has released a statement on the matter.
"The vast majority of Nintendo Switch games will support Save Data Cloud backup. However, in certain games this feature would make it possible to, for example, regain items that had been traded to other players, or revert to a higher online multiplayer ranking that had been lost. To ensure fair play, Save Data Cloud backup may not be enabled for such games. To ensure that Save Data Cloud backups cannot be used to unfairly affect online multiplayer rankings, the feature will not be enabled in Splatoon 2."